Wang Wen-Qiao, Ma Zhi-Qiang, Han Xiu-Ying, Zhang Xiao-Feng, Chen Shu-Long
Plant Protection Institute, Hebei Academy of Agricultural & Forestry Sciences, Baoding 071000, Hebei, China.
Meded Rijksuniv Gent Fak Landbouwkd Toegep Biol Wet. 2002;67(2):307-14.
In vitro, isolates resistant to metalaxyl (M) and oxadixyl (O) of Phytophthora infestans were 11.2% of 62 isolates from potato and tomato in Hebei Province, mean resistance factor was 15,022 fold and 24,733 fold, respectively, no isolates resistant either to cymoxanil (C) or to dimethomorph (D) were detected. On the other hand, in vivo, isolates resistant to M and O were 29.0% and 32.7%, respectively, among 217 isolates from potato plants in Weichang and Chongli, Hebei, only one isolate resistant to M and O was found among 88 isolates from tomato plants in Xushui, Hebei. Among 73 isolates from potato in Weichang and Chongli, 6 isolates with A2 mating type were 8.2%, 3 A2 isolates resistant to metalaxyl and oxadixyl. 3 A2 isolates were 6.8% of 44 isolates from tomato in Xushui. Cross resistance in Phytophthora infestans was confirmed between M and O, but no cross resistance between C or D and M or O. The field isolates resistant to M and O were outstandingly fitter than sensitive or intermediate ones, mainly due to stronger sporulation capacity of the field isolates.
在体外，对甲霜灵（M）和恶霜灵（O）耐药的致病疫霉分离株占河北省62株马铃薯和番茄分离株的11.2%，平均耐药系数分别为15,022倍和24,733倍，未检测到对霜脲氰（C）或烯酰吗啉（D）耐药的分离株。另一方面，在体内，来自河北围场和崇礼马铃薯植株的217株分离株中，对M和O耐药的分离株分别占29.0%和32.7%，在河北徐水番茄植株的88株分离株中仅发现1株对M和O耐药。在围场和崇礼马铃薯的73株分离株中，6株A2交配型分离株占8.2%，其中3株A2分离株对甲霜灵和恶霜灵耐药。3株A2分离株占徐水番茄44株分离株的6.8%。致病疫霉中M和O之间存在交叉耐药性，但C或D与M或O之间不存在交叉耐药性。田间对M和O耐药的分离株比敏感或中间型分离株适应性更强，主要是因为田间分离株的产孢能力更强。
